Hi Lily, You can ignore the first three lines, they are just for information. Which version of raster do you have? I see that the attempt to read the crs-variable was not wrapped in a try-call in earlier versions. Upgrading might help.
Best, Jon On 7/27/2016 5:13 PM, lily li wrote: > Hi Jon, > > I still have problems. The brick function does not work well and I > don't know where to check the problem. I put the error message below, > thanks. > > > pre = brick("~/Downloads/sample_precip_daily.nc > <http://sample_precip_daily.nc>") > [1] "vobjtovarid4: error #F: I could not find the requsted var (or > dimvar) in the file!" > [1] "var (or dimvar) name: crs" > [1] "file name: /.../Downloads/sample_precip_daily.nc > <http://sample_precip_daily.nc>" > Error in vobjtovarid4(nc, varid, allowdimvar = TRUE, verbose = verbose) : > Variable not found > > > On Wed, Jul 27, 2016 at 1:10 AM, Jon Skoien > <jon.sko...@jrc.ec.europa.eu <mailto:jon.sko...@jrc.ec.europa.eu>> wrote: > > I think you get the error because you passed the object from > nc_open(), you should rather pass the filename of the netCDF, so: > > pre = brick("sample_precip_daily.nc <http://sample_precip_daily.nc>") > From the test-file, this gives you a RasterBrick-object with 5*9 > pixels and 7305 layers. > Then you can extract data.frames of each layer with: > dframe = rasterToPoints(pre[[1]]) > where 1 is the first layer, or time series with: > tseries = pre[3,4] > where 3 and 4 are the pixels in x and y-direction. > > To write dframe to csv: > write.csv(dframe, filename = "csvfile.csv") > Check the function for more options. > > Hope this helps you a bit further. > Jon > > > On 7/26/2016 9:07 PM, lily li wrote: >> Thanks for your reply. But it says "Error in (function (classes, >> fdef, mtable)): >> unable to find an inherited method for function 'brick' for >> signature 'ncdf4' " >> >> The dataset is attached. It contains daily precipitation data for >> 20 years, within a rectangle, so that there are several grid >> points. I use the code to open it, but don't know how to get csv >> files, while each file contains continuous daily precipitation >> data for each grid cell. >> pre1 = nc_open('sample_precip_daily.nc >> <http://sample_precip_daily.nc>') >> pre1 >> pre1_rd = ncvar_get(pre1, 'precipitation') >> nc_close(pre1) >> >> Thanks for your help. >> >> On Tue, Jul 26, 2016 at 4:08 AM, Jon Skoien >> <jon.sko...@jrc.ec.europa.eu >> <mailto:jon.sko...@jrc.ec.europa.eu>> wrote: >> >> You could try with the brick function from the raster package. >> >> bvar = brick(netcdfName) >> >> This uses the ncdf4 functions for opening and reading the >> netcdf, but makes it easier to extract data for each day: >> >> p1 = rasterToPoints(bvar[[1]]) >> and write p1 to csv. >> >> Best, >> Jon >> >> >> >> On 7/26/2016 6:54 AM, lily li wrote: >> >> Hi all, >> >> I have a problem in opening netcdf files. If one netcdf >> file contains >> longitude, latitude, and daily precipitation. How to >> relate each >> precipitation record to its associated location, and >> export them as csv >> files? Thanks. >> >> I just use nc_open(), ncvar_get(), but it is not very >> helpful. Thanks for >> any ideas. >> >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> R-help@r-project.org <mailto:R-help@r-project.org> >> mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide >> http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, >> reproducible code. >> >> >> -- >> Jon Olav Skøien >> Joint Research Centre - European Commission >> Institute for Space, Security & Migration >> Disaster Risk Management Unit >> >> Via E. Fermi 2749, TP 122, I-21027 Ispra (VA), ITALY >> >> jon.sko...@jrc.ec.europa.eu <mailto:jon.sko...@jrc.ec.europa.eu> >> Tel: +39 0332 789205 <tel:%2B39%200332%20789205> >> >> Disclaimer: Views expressed in this email are those of the >> individual and do not necessarily represent official views of >> the European Commission. >> >> > > -- > Jon Olav Skøien > Joint Research Centre - European Commission > Institute for Space, Security & Migration > Disaster Risk Management Unit > > Via E. Fermi 2749, TP 122, I-21027 Ispra (VA), ITALY > > jon.sko...@jrc.ec.europa.eu <mailto:jon.sko...@jrc.ec.europa.eu> > Tel:+39 0332 789205 <tel:%2B39%200332%20789205> > > Disclaimer: Views expressed in this email are those of the individual and > do not necessarily represent official views of the European Commission. > > -- Jon Olav Skøien Joint Research Centre - European Commission Institute for Space, Security & Migration Disaster Risk Management Unit Via E. Fermi 2749, TP 122, I-21027 Ispra (VA), ITALY jon.sko...@jrc.ec.europa.eu Tel: +39 0332 789205 Disclaimer: Views expressed in this email are those of the individual and do not necessarily represent official views of the European Commission. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.